1. Field of the Invention
The present invention relates to the elimination of contaminants from soils and, in particular, to the elimination of organic compounds by biological degradation.
2. Brief Description of the Prior Art
It is known in the art that soils contaminated with various organic compounds can be treated with certain "land farming" techniques to eliminate the contaminants by biological degradation. That is, the soil to be treated is layered over a base surface and the growth of microorganisms capable of degrading the contaminants is encouraged in the soil by providing favorable moisture, nutritional and aeration conditions.
Precipitation may result in excess moisture which may tend to form in ponds on the surface of the soil layer. Excess moisture may also migrate vertically downwardly toward the water table and thereby spread contaminants with it. Depending on the amount of local precipitation and the particular characteristics of the soil being treated, it is, therefore, often necessary to provide a plastic liner beneath the soil being treated to prevent such downward migration of moisture.